Mechanism for heat sealing package seam joints



Jan. 1948. H. OQIRMSCHER 2,434,657

mcnmxsu FOR HEAT SEALING PACKAGE smm JOINTS,

Filed July 16, 1941 2 Sheets-Sheet 1 12 HANS o. mMscHEI? ATTORNEY i atented 5. 2%, 14%

MECHANISYVE FOR HEAT SEALING PACKAGE SEAM JOINTS Hans 0. Irmscher, Roslyn, N. Y., assignor to National Urn Bag Company, a corpora tion oi New York Application July 16, 1941, Serial No. 402,635

11 Claims. (Cl. 154- 12) This invention relates to the manufacture of filled containers or bags and more particularly is directed to portions or mechanisms of machines such as used for making filled bags, tea-balls or similar infusion packages in which the bag seams are formed with heat sealed closure joints.

Among the objects of the invention is to generally improve portions of a mechanism of bag packaging and tea-hall making machines of the character described, which shall comprise few and simple parts that are easy to assemble, which shall be readily incorporated in various types of partly and fully automatic existing packaging machines producing filled bags, tea-balls and the like articles for replacing the usual seam joint sewing and stapling devices, which shall also be adapted to incorporation as part of newly constructed high-speed packaging machines and when so incorporated in either existing or newly constructed machines permitting an increase in the normal output capacity thereof, and which shall be practical and eflicient to a high degree in operation.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combinations of elements and arrangement of parts which will be exemplified in the construction hereinafter described and of which the scope of application will be indicated in the following claims.

In the accompanying drawing in which is shown a possible illustrative embodiment of the invention,

Fig. 1 is a side elevational view of part of an automatic tea-ball manufacturing machine showing a top closure heat sealing mechanism incorporated therein to embody the invention;

Figs. 2 and 3 are sectional views taken on lines 2--2 and 34, respectively, in Fig; l, the heat sealing clamping means of said mechanism being shown in Fig. 2 in effective closed position;

Fig. 2a is a fragmentary view of the clamping means shown in Fig. 2 in an operative open position prior to or following that shown in Fig. 2; Fig. 4 is a cross-sectional view taken on line 4-4 in Fig. 3; and

Fig. 5 is an enlarged detailed top plan view showing the top closure heat sealed seam joint of the tea-ball formed by the improved mechanism shown in Figs. 1 to 4, inclusive.

In my co-pending application, Serial No. 402,634, filed simultaneously herewith, now Patout No. 2,376,360. dated May 22, 1945, there is disclosed an improvement in the manufacture of filled containers or packages and more particularly a novel mechanism for making folded heat sealed bottom seam joints of package bags for infusion packages, such as tea-balls or the like. The present invention is directed more particularly to an improved mechanism incorporated in such machines for forming a heat sealed top closure joint. Sincesuccessful and practical commercial utility for the latter improvements depends on its adaptability to large scale quantity production of such packages on automatic machines, the present invention contemplates the incorporation of the improved heat sealed top closure seam joint mechanism in automatic machines of any of the various existing types. To this end there is shown in the drawing and described hereinafter the incorporation of the present invention in a high-speed fully automatic tea-ball machine constructed, for example, like that of the co-pending application of Mervin Allatt, Serial No. 37,257, filed August 21, 1935, now Patent No. 2,290,158. Only fragmentary portions of the Allatt machine are included herein as will enable the different features of the invention to be understood and except as to the details of the construction and the mode of operation to be pointed out. the portions of the bag forming machine may be as shown in the machine illustrated in said Allatt patent, to which reference may be had for a complete description thereof. It is to be understood, however, that the invention is equally applicable to incorporation in other "and various types of packaging machines.

Referring nowto the drawing NJ denotes a mechanism for heat sealing the top closure joint J of a partially filled bag. as for example, the tea bag T which previously on another part of the machine (not shown) has been formed from a tubular sheet material M having a heat sealed edge joint E and aheat sealed upfolded bottom closure joint S, said mechanism ll) being mounted on a stationary portion of the machine B by fastening bolts H and being supplied with top open ended filled bags by a suitable transfer carrier portion C,- a fragmentary portion of which is shown in Fig. 1. Full details of the construction and a complete description of the operation of such carrierC are given in the above-mentioned Allatt patent.

The tubular sheet material M of which the tea bag is formed may be of foramlnous construction,

such asfilter paper. perforated parchment paper or Cellophane, cotton gauze or the like. That used in the practice of the invention here described is a filter paper base layer coated on one side with a thermosetting "partially fused plastic lamina for forming the heat sealed border joint of the package bag being manufactured. If desired, the tubular-sheet material M may be made from a continuous web of filter paper of suitable dimensions folded over on itself, said web having.

' the "partially fused" plastic lamina coating on the inner surface with the marginal edges thereof in contact and folded over and creased to form a seam joint. n heat sealing, the entire length of' said folded creased seam joint of the tubular sheet material M may be sealed as at E, as shown in Figs. 1 and 4.

The carrier 0 may be constructed to have a Thebowed springs 2| and 22 as shown in Fig.

' 2a are symmetrically curved and have their step by step movement,the operation taking place in timed relation with the mechanism l0 so that the open ended filled bag M is brought to rest during the intermittent movement of the machine operations between a pair of heated, .pressure jaws l2 and i3. Heat is-lsupplied to each of said jaws by suitable mean'Sq ibedded therein, such as electric heater H,the teinp erature of said heaters H being controlled and regulated by a suitable thermostat regulator R. Said heaters H and regulator R may be of any well understood construction and may be interconnected through a wiring installation in the well understood manner comprising conduit fitting 1?, wire W and a junction box F, as shown inJFigs. 1 and 2.

The mechanism l0 comprises, besides the jaws i2 and |8,,a base fitting M, which is secured by said bolts II to the machine frame B and has a horizontally disposed integrally ribbed extension I ia which terminates-in a bearing support 14b located as seen in Figs. 1 and 3 justbelowthe end of the carrier C. .Throughsaid bearing support Mb extends a horizontally disposed shaft i5 rounded contacting spaced ends 2la and 22a. respectively, extended outwardly beyond the surfaces |2a and i3a, respectively. Said spring ends 2|a and 22a, however, are normally spaced apart when the jaws l2 and I3 are in ful'y open position to allow free passage of the open end portion of the tea-ball bag to be advanced and aligned by the carrier 0 between the jaws I2 and iii.

The lower arm ends i611 and Ila each carry stub shafts "id and i'ld, respectively, projecting therefrom over the base fitting l4. Rollers 24 and- 25 are mounted for rotation on, and are retained against displacement from said shafts "id and lid, respectively, by washers 21 and cotter pins 28. Said rollers 24 and 25 engage in spaced angularly disposed slots 29a and 29b. respectively, of reciprocably mounted rack bar 29 in a slideway I40 which may extend at right angles to the axis of base fitting extension a, the fitting it being provided with an enlarged integral portion hid in which said slideway He is formed, a cover plate l4e' fastened by screws Hf confining the rack'bar 29 in said slideway llc, as shown in Figs. 1, 3 and 4.

The rack bar 29 may terminate at a spaced distance from said slots 29a and 29b in a forked connection 29c which is adapted to enga e with an actuating shift rod Q, the latter being operated intirned relation with the advancing movement through the machine of the tea-balls T on the carrier 0, such actuation of rack bar 29 by said shift rod Q being shown and indicated in dotted lines-in Fig. 3. To further assist in urging the jaws l2 and I3 to be in efiective pressure position. said rack bar 29 may be provided with an on the opposite end portions of which and separated by the intermediate bearing support Mb are mounted for swinging movement upstanding arms l6 and I1 by lower or bearing ends Ito and |'la,-respectively. The lower arm ends iiia. and l'la maybe retained against displacementfrom off their respective ends of shaft l5 by providing a headed portion |5a for confining the arm end Ila and a pinned collar |5b for the arm end |6a as shown in Fig. 3. The arm H5 at its upper or free end Eb carries the jaw |2 which is secured implacej by suitable fastening means, such as screws Id. The arm I! at its upper or free end llb extends .utwardly over said carrier C and has secured by screws IS. the jaw iii in cooperative alignment with the jaw l2. ,There is also provided posts I60 and He upstanding from upper arm ends liib and ill), respectively, to which the opposite ends of a coil tension spring 20 are anchored to extend the latter horizontally'above the arm end ilb. Said spring 2|) serves to con stantly Tirge the jaws l2 and i3 on arms l6 and I! to coact toward each other.

As seen from Figs. 1, 2 and 2a, the

and Ho, respectively, by suitable fastening means such as spaced screws 23.

jaws i2 and i3 maybe formed with corrugated mating surfaces I21; and l3a. respectively, so as to imextending post 3| on which one end 32a of a tension spring 32 is anchored, the other end being secured to a relatively stationary part of the machine (not shown) in the well understood manner. Said spring 32 is constructed and arranged to urge the rack bar 29 into its extended slidable position, shown in full lines in Fig. 3, and counteracts the movement of the shift rod R, to swing the jaws l2 and i3 open.

With the parts constructed, assembled and incorporated in a package machine as described above and shown in the drawing, the operation thereof will now be readily understood. The carrier C which is supplied with .a succession of open ended partially filled tea bags bring by a step' by step advance movement an open ended portion J of the tea bag between the spread springs 2| and 22 are then separated sufiiciently 'to permit said bag end portion J,| to pass therebetween. When said bag end portion J on the carrier C is brought to rest in alignment with the jaws l2 and I3, the rack bar 29 is shifted by the rod Q from the dotted line to the full line position shown in Fig. 3. This shifting movement swings arms l6 and i1 toward each other to close the jaws l2 and I3 for clamping bag end portion J l and when electric power is supplied to heaters H, a heat sealed top closure joint J is provided. It will be noted from Figs. 2 and 2a that in the closing movement of the jaws l2 and i3, the springs 2| and 22 are first to contact the spaced rounded cooperative ends 2|a and 220. against the sides of the open end portion J| to stretch said bag end portion J| smooth forming a temporary closure and retaining same for the heat sealing action by jaws i2 and I3, thus eliminate ing possible crumplins or creasing of the material at said bag closure end portion and assuring-a perfectly formed heat sealed joint J; Afterthe jaws l2 and II have heat sealed the joint J they are again separated by shifting of the rack bar 29 to the dotted line position shown in"Fig. 3 against the action of spring 32 forswingin the arms 16 and I1 away from each other'against the action of the spring 20 to open the jaws l2 and i3. 'The jaws l2 and I3 on being again separated, carry the springs 2| and 22 to clear the passage for the finished tea-ball T permitting the carrier C and said finished tea-ball T with the c.0sure joint J to be discharged from the machine, if desired, or to pass to 'a string handle applying mechanism (not shown) as provided in said Allatt patent. On advancing said finished teabali T beyond mechanism iii, the carrier C positions another open end portion Jl of a partially filled tea bag between the jaws l2 and I3 and the heat sealing operations above described are repeated as a continuous cycle of operations.

It will thus be seen that there is provided a mechanism in which the several objects of this invention are achieved and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiments above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters'Patent:

1. A mechanism of the character described comprising a base fitting, a pair of spring pressed arms pivotally mounted on said fitting for swinging movement to and away from each other, a

pair of pressure jaws carried by said arms, heating means for said jaws, spring means carried with said jaws by the arms for stretching smooth open ends of package bags inserted therebetween to 'temporariiy retain said open ends as closures,

and means for mounting said spring means and pressure jaws on the arms whereby said spring means and pressure jaws are effective in succeshe lamina, a mechanism comprising means co- 5. In the combinatii n defined in claim 4 in which both of said means are incorporated into the mechanism to operate together by a single actuating means. 1

6. In the packaging machine defined in claim a in which said pressure, sealing means has mounted for movement therewith the stretching means, the latter being positioned for effective operation prior to forming the heat sealed edge joint.

'7. In a package machine of the character described, a carrier for advancing through the machine in succession filled package bags having open ended portions coated on the inner surface side thereof a thermosetting. plastic lamina, a

mechanism comprising means having effective spaced apart portions for stretching each'of said bags to'form a smooth tight temporary closure with the lamina on said inner side in face to face contact relation inwardly of said open ended portions, means for pressure heat sealing said open ended portions beyond said temporary closure while retaining said stretching means efiective during the formation of a heatsealed edge joint, and means for actuating said stretching: and

' pressure heat sealing means connected to operate in timed relation with the carrier advancing movement, the stretchingmeans being positioned to be efiective during the actuation of the sealing means and before the final operation thereof.

sion to form a heat sealing joint at said open ends upon actuation of said arms.

2. A mechanism of the character described comprising a base fitting, a pair of spring pressed arms pivotally mounted on said fitting for swings ing movement, a pair of pressure jaws carried by said arms, heating means for said jaws'. a rack movably mounted on said fitting and connecting with said arms for swinging said jaws to and away from each other, spring means having 00- operating spaced apart effective portions carried with said jaws by the arms for stretching smooth open ended portions of package bags inserted in a path between said jaws and spring means when swung to an open position, said spring means in said open position being extended into said path beyond the jaws to effect a temporary closure for said open ended portions prior to heat sealing thereof by the jaws.

3. The mechanism defined in claim 2 in combination with a carrier for advancing package bags with said open ended portions through. a

machine in timed relation with respect to the 8. In combination with a carrier of a packaging machine for advancing filled package bags having heat scalable open ended portions, of a pair of pressure jaws, arms pivotally mounting said jaws for swinging movement to and away from each other ppsitioned along the path of travel of said bag open ended portions, heating means incorporated in said jaws, and a pair of springs mounted for swinging by the arms with said jaws, said springs having cooperating spaced apart effective portions normally extending closer to the path of travel of said open ended portions than said jaws when in open position for forming.

smooth closures on said open end portions inwardly of outer edges thereof preparatory to and during the pressure heat sealing action by said jaws at said edges and beyond said closures.

9. A mechanism of the character described v comprising a base fitting, a pair of pivoted spring pressed'arms carried by said fitting, cooperating separable pressure jaws terminating said arms mounted for swinging movement to and away from each other, heating means for said jaws,

a pair of springs carried by said arms adjacent the jaws, said springs having spaced apart contacting ends for gripping and smooth stretching open ends of package bags inserted between said separable jaws to retain saidends as temporary complete closures across the entire width of the bags, and

' means for mounting said springs and said jaws on the arms whereby said springs and jaws are effective in succession for forming heat sealed v 7 joints at the edges of said open ends upon tu tion of said arms.

10. A mechanism of the character described comprising a. pair of pressure jaws pivotally mounted for swinging movement to and away from each other, heating means for the jaws to provide a heat sealed joint at an open end portion of a package bag when inserted between and clamped by said jaws, and spring means having,

spaced cooperating portions carried with the jaws and normally positioned to partially project into a path of movement of said bag open end portion to form a smooth temporary closure prior to and during the clamped heat sealing action of said jaws.

11. The mechanism defined in claim 1 in combination with a carrier means for advancing package bags with top open ends in unrestricted positions and in timed relation with respect to the swinging movement of said arms and jaws, and the forming of a smooth temporary closure prior to and during the clamped heat sealing action or said laws by said spring means.

HANS O. IRMSCHER.

REFERENCES CITED 

